Conventionally, in electrically-driven vehicles such as an electric vehicle, a hybrid vehicle and the like, a motor is used to drive those vehicles by using an electric energy supplied from a battery or the like. The electric energy required for air-conditioning in the vehicle is also supplied from the battery. Thus, in summer and in winter during which a large amount of energy is required for the air conditioning, a cruising range of the electric vehicle may decrease.
For avoiding such a drawback, for example, patent document 1 proposes a technique that stores heat (i.e., thermal energy) in a heat storage device or in a cold storage device for using the stored heat during a vehicle running. However, in such technique, a large amount of a heat storage material or a cold storage material is required, thereby causing an increased vehicle weight or a large installation space in the vehicle.
Therefore, for example, patent documents 2 to 4 propose a technique of using heat capacitive elements such as a battery for storing heat (i.e., thermal energy), instead of using the cold storage device or the heat storage device.
In the patent document 2, a heating assist technique is disclosed in which the heat generated by a battery is introduced into the vehicle compartment and the introduced heat is used for assisting a heating capacity.
The patent documents 3 and 4 describe about a heating/warming up of a battery and a heat storage in the battery by utilizing a heat generation due to a resistance of the battery in a battery charging time as well as utilizing a switching element that serves as a heat generation facilitation device. Further, there are described that conditioned air in, for example, a house is sent to a battery through a hose or the like, so as to control a battery temperature. In addition, there are described that a cold storage material is contained in a container of a battery to store a cold energy (i.e., a cool air energy) by using a refrigeration cycle in the battery charging time, and then to cool air inside the vehicle compartment through a coolant in a vehicle running.
According to the conventional art of the patent documents 2, the heat generated by the battery in the vehicle running and the battery charging time is used for heating. However, such heating capacity may be difficult to be obtained because it does not necessarily provide sufficient energy for heating the vehicle compartment especially in winter during which temperature difference between the battery temperature and the temperature of the inside air in the vehicle compartment is not large enough for providing a required amount of heat.
Although, the patent documents 2 provides a configuration of how to use the introduced heat for heating, it is silent about how to, for example, use the cold energy that is stored in the cold storage device such as a battery for cooling the air. Further, in the patent document 2, although heat generated by the battery at the vehicle running time and at the battery charging time is used for air-conditioning, a positive use of the battery for storing the heat energy and the cooling energy is not disclosed. That is, the heat capacity of a large capacity battery is not fully utilized in the patent document 2.
According to the conventional art of the patent documents 3 and 4, in addition to the same problem as the conventional art of the above-mentioned patent document 2, a temperature difference between the battery temperature and an inside air temperature of the vehicle compartment is also not sufficient in a cooling operation, which leads to an insufficient cooling capacity of the cooling operation. Further, even when the in-house air is introduced to the vehicle, the same problem of insufficient temperature difference is caused, and thereby it may difficult to obtain a sufficient heating/cooling capacity. Further, for the air introduction directly into the vehicle from the house, a hose is required, thereby complicating the structure of such system.
Further, although the patent documents 3 and 4 describe a method of how heat (i.e., thermal energy) at the charging time is stored in the battery (i.e., heat capacitive elements), the patent documents 3 and 4 fail to describe a method of how a remaining heat in the vehicle is stored in a running-related component such as a battery or the like. Further, although the patent documents 3 and 4 have a description about a control flow of pre-air-conditioning, the control flow for accumulating heat (i.e., thermal energy) in a battery (i.e., heat capacitive elements) is not disclosed.